1. Technical Field of the Invention
The present invention relates to a telecommunications network and, in particular, to the provision of service area dependent subscriber data to a serving mobile switching center (MSC) within a Public Land Mobile Network (PLMN).
2. Description of Related Art
With the advent and development of mobile telecommunications systems, telecommunications users are no longer physically bound to wireline terminals or fixed locations for telecommunications network communications. Using the added capabilities of roaming and interoffice handoffs, mobile subscribers may travel between multiple Public Land Mobile Networks (PLMNs) utilizing the same telephone number and the same mobile station to originate outgoing calls and to receive incoming calls. Thus, a mobile subscriber may access telecommunications service from multiple locations utilizing multiple service providers with any incurred fees being charged to a single subscription. Furthermore, calling parties do not necessarily have to know where the mobile subscriber is physically located in order to properly route and to establish a call connection. Data signals between visitor location registers (VLRS) and a home location register (HLR) automatically update and store subscriber information enabling the network to reroute incoming calls to the appropriate mobile switching center (MSC) serving the roaming mobile subscriber. Furthermore, regardless of which MSC is currently serving the mobile station, the VLR associated with the serving MSC communicates with the HLR assigned to the mobile station to retrieve the requisite subscriber data, including subscriber feature data and billing data, and provide uniform mobile service to the mobile station.
However, such uniformity in service is not always desirable for a subscriber who has a subscription obligation with a service provider. A mobile subscriber may have a call forwarding feature, such as Call Forwarding on Busy (CFB), activated towards a particular forward-to-number. If the forward-to-number is within the same local access transport area (LATA) as the mobile subscriber's home public land mobile network (PLMN), all incoming calls forwarded by the home PLMN to the specified forward-to-number are considered as local calls. However, if the mobile subscriber is traveling outside of his home PLMN area, the calls forwarded by the serving MSC to the specified forward-to-number are considered as inter-LATA calls and may incur unwanted long distance charges. For example, if the mobile subscriber is a New York resident having a subscription with a New York mobile service provider and has a New York wireline terminal as his or her CFB forward-to-number, any calls received by the serving New York MSC while the mobile subscriber is already busy are forwarded to the specified New York forward-to-number. Similarly, even if the mobile subscriber is traveling outside of New York and is being served by a visited New Jersey MSC, the incoming calls are still forwarded by the visited MSC to the previously designated New York forward-to-number. Unfortunately, such a long distance call connection between the New Jersey MSC and the New York forward-to-number may incur unwanted long distance charges for the mobile subscriber. However, the mobile subscriber is not conventionally able to avoid such an unfavorable billing practice by assigning a first forward-to-number while being served by a New York MSC and a second forward-to-number while being served by a New Jersey MSC.
As another example of not wanting to provide such uniformity in service to a roaming mobile station within a mobile network, the mobile subscriber might want to activate different subscriber features using different subscriber data when he or she is in one PLMN versus another PLMN. For example, if the subscriber is using mobile service within his or her home PLMN, the subscriber might want to charge the calls to his or her private subscription. However, if the subscriber is traveling within a particular service area outside of his or her home PLMN, the subscriber might want to charge the calls received or originated within that service area to his or her business subscription. As another illustration, the subscriber might only want to allow call waiting (CAW) when the subscriber is in one particular PLMN and disable the feature when in another PLMN.
Accordingly, there is a need for a mechanism to enable the mobile telecommunications network to selectively provide service area dependent subscriber data to a mobile switching center (MSC) serving a particular mobile station and to enable the serving MSC to provide service area dependent mobile service to the mobile station.